A Catalogue of Ultracompact Mass-Transferring White Dwarf Binaries

TL;DR

This paper compiles a comprehensive catalogue of all known ultracompact white dwarf binary systems with mass transfer and orbital periods under 70 minutes, serving as a key resource for researchers in the field.

Contribution

It provides the first detailed, publicly accessible catalogue of ultracompact mass-transferring white dwarf binaries, including data, properties, and recent updates.

Findings

Includes 123 confirmed binaries and 29 candidates.

Summarizes observed properties like orbital periods and stellar masses.

Provides a platform for tracking the current research status.

Abstract

We present an overview and catalogue of all known mass-transferring binary systems that have white dwarf accretors and orbital periods shorter than 70 minutes, including the AM CVn-type binary systems and a number of related objects. In this paper, we provide an overview of the literature background and describe recent breakthroughs, open questions, and connections to other fields. This overview is intended to provide a starting point for researchers who are relatively new to the fields of ultracompact binaries or AM CVn-type binaries. We define the scope of the catalogue (the criteria for inclusion) and describe its format and contents (what data have been included for each target). We also summarise the observed properties of the known mass-transferring ultracompact binaries, including their orbital periods and component stellar masses and radii. The catalogue presented here aims to provide a central resource to enable researchers to track the current status of the known sample. At the time of writing, the catalogue includes 123 confirmed binaries and 29 candidates. The catalogue is hosted on a public platform (Zenodo) with version control, and will be updated regularly.